You said:
Then you said:
In one place, there wasn’t a space between the verse number and the first word of the verse. That may have been the issue.
To me that is a direct correlation.
It may not have been the only error, but it was one show stopper for sure.
Paratext is powerful. If you are typesetting with a Xetex based tool (PTXprint), then take the time to set up Paratext and use its power to clean up your text/syntax. Then your tool should work.
Your error would also come up in Schema check. Hold down shift while clicking on the Basic Check item and the Schema check shows up. Schema Checks can be scary, as one error can produce many error messages.